1. Technical Field
The present invention relates to the field tools used to remove a typically brass or bronze injector sleeve from a cylinder head in a diesel engine. These sleeves are press fit into a bore in the head. After years of use the sleeves will loosen or begin to leak and need to be replaced.
2. Description of the Related Art
Tools for the removal of injector sleeves have been described and patented in recent years. U.S. Pat. No. 5,784,783 by Carpenter for METHOD OF REMOVING AND INJECTOR SLEEVE issued on Jul. 28, 1998 claims a tool wherein one inserts rounded head into the sleeve. A cylinder with a reverse tapered edge is forced down onto the top edge of the sleeve. This flairs the top edge inward, thus capturing the rounded head within the sleeve. The rounded head is pulled up and the intent is that the flair will hold tight to the rounded head and the sleeve will be pulled out with it. This design has some inherent flaws. First, the flaring process forces the sleeve into the head even tighter than it would initially be. Second, if the sleeve is tight, as one would expect, the flair is likely to weaken and pull apart, whereupon, the rounded head comes out but the sleeve has been seated even tighter.
U.S. Pat. No. 5,090,102 by Lovell for DIESEL INJECTOR SLEEVE REMOVER issued on Feb. 25, 1992 claims a hollow, externally threaded tube which has been slit down one side. A rod is inserted in the tube which is conical at the bottom end. The rod sticks out of the slitted threaded end of the tube and the large end of the rod is a little larger than the threaded tube. The top end of the rod is connected to a slide hammer. The threaded sleeve is inserted into the sleeve. One tap of the hammer seats the threads of the tube into the bore of the sleeve because tapping the hammer down against the top of the sleeve forces the sleeve down onto the conical end of the rod and this causes the threaded tube to expand, thus forcing the threads to grab into the bore of the sleeve. Now the slide hammer is pulled up to drive the assembly out along with the sleeve. The primary weakness of this design presents itself in the case where the sleeve is very tightly held within the cylinder head. The threads won't have a strong enough hold and will simply chew and pull material out of the sleeve but leave the sleeve in place in the head.